The owners of the New York Islanders have been trying to sell a minority stake in the NHL club for months — but have not had any luck, The Post has learned.

The owners, Jon Ledecky and Scott Malkin, are looking to sell a 15 percent stake at a $500 million valuation, three sources close to the situation said.

The duo bought a controlling stake in the team in 2014 for about $485 million.

However, without a permanent home and without access to valuation naming rights and luxury suites, Forbes valued the team last fall at just $385 million — perhaps making the owners’ valuation a bit rich.

Part of the issue for suitors is that it is not clear where the Islanders will be playing after the 2018-19 season, sources said.

Mikhail Prokhorov’s Barclays Center is not interested in keeping its lease with the Islanders after two more seasons because of the onerous terms of the deal. Barclays pays the Islanders $53.5 million in guaranteed fees each season — making it difficult to make money off ticket and suite sales, sources said.

The Islanders, from their perspective, are not happy with ice conditions.

There is an out in the lease after two more seasons.

The Islanders have no clear alternative: The owners have been considering building an arena near Belmont Racetrack, but the state has not yet moved forward in asking for site proposals, sources said.